Skill-based errors – slips and lapses – when the action made is not what was intended

Rule-based mistakes – actions that match intentions but do not achieve their intended outcome due to incorrect application of a rule or inadequacy of the plan.

Knowledge-based mistakes – actions which are intended but do not achieve the intended outcome due to knowledge deficits.

Examples:
Click on each of the images below to see examples.

Also used occasionally is the term “strong but wrong.” This refers to erroneous behavior that is in keeping with past practice rather than current circumstances. This type of error is very difficult to overcome, as people who have positive experience with a particular behavior can be very confident in their actions under slightly different circumstances, even when those actions are wrong.

Check your understanding:Classify each of the following errors by reason’s levels.

Skill-based

Rule-based

Knowledge-based

Taking the turn to go to work on your day off, when you intended to go elsewhere